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Some Considerations for MICE TOF Stations FE electronics (mainly TOF0). M. Bonesini INFN Milano. Outline. rate considerations mainly for TOF0 readout electronics Cables Discriminators FE schemes: TDC only or TDC+QADC BTF testbeam plans Conclusions.
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Some Considerations for MICE TOF Stations FE electronics (mainly TOF0) M. Bonesini INFN Milano M. Bonesini 10-02-06 DAQ Meeting
Outline • rate considerations mainly for TOF0 • readout electronics • Cables • Discriminators • FE schemes: TDC only or TDC+QADC • BTF testbeam plans • Conclusions M. Bonesini 10-02-06 DAQ Meeting
Rates (Singles per ms) target insertion reduced to get 600 good mu+/sec (AUG05) M. Bonesini 10-02-06 DAQ Meeting
TOF0 AUG05 beamline:news from 21/10/05 from T. Roberts 6pi beam M. Bonesini 10-02-06 DAQ Meeting
1pi beamline design from D. Adams M. Bonesini 10-02-06 DAQ Meeting
What does it means for a single TOF channel ? • From D. Adams & T. Roberts we can expect a rate ~.5 MHz/ch at TOF0, ~.25 MHz/ch at TOF1, ~.2 MHz at TOF2 • PMTs must sustain high rate, eg high average anode current. Fine for TOF0 with R4998 + active divider • FE + DAQ must cope with rate: ie conversion time ~1-2 ms, ~1000 events buffering M. Bonesini 10-02-06 DAQ Meeting
Cables/Splitters • output PMT signal on RG213 cables with BNC connectors (~50 cm RG274 cable from PMT, patch panel, RG213 ~35 m long) • RG213 differential variation with temperature 30 ppm/C as measured in HARP (3 times less than conventional RG58 cables) • Available cables 40 m long: problem if we need much shorter ones (we have to cut/reconnectorize them) or longer ones (extra cost ~10KE) • Depending on discriminator choice (CF vs L.E. or ALICE integrator solution) splitter can be needed • active splitter (recuperated from Harp: ~100 ch) maybe a choice TDC L.E. discrim PMT signal splitter QDC M. Bonesini 10-02-06 DAQ Meeting
Discriminator choice Choice between: • CF discrimininator : no need of time-walk correction no QDC line/splitter needed, but st is usually worse • L.E. discriminator: st is usually better, but a QDC is needed • ALICE NINO chip: it includes a discriminator + an integrator to make possible TOT correction (slightly equivalent to p.h. correction). According to ALICE coll. solution 3 is equivalent to 2 Problem: while solutions 1-2 are commercial ones (CAEN or …); solution 3 needs some R&D M. Bonesini 10-02-06 DAQ Meeting
ALICE NINO Chip (info from JS ) Measure the Charge with Time Over Threshold Principle • Advantage: Easy Cabling andCharge Measurement (not linear though)Good Precision for Time Walk Correction • NINO = ASIC developed by CERN/MIC for Alice TOF Discriminator with ToT “proportional” to the Charge (at low amplitude): provides 50 ps resolution (IEE TNS Vol 51-5 (2004) 1974-1978) • Drawback : Requires Board development ! • Cost: board production + development ~ 20 K TDC PMT NINO Rising edge + Trailing edge Time Measurement Trigger Logic Width ~Charge M. Bonesini 10-02-06 DAQ Meeting
TDC choice • Standard CAEN V775 TDC (HARP like) are not viable due to long conversion time (2.x ms) and small memory buffer (32 evts) • We plan to use CAEN V1290 multi-hit TDC: continuos operating mode, leading/trailing edge operations, 1000 evts buffer memory • Problems: V1290 is not an easy object to handle. 1 module just delivered in Milano, we plan to use it at BTF and compare performances with V792+V775 M. Bonesini 10-02-06 DAQ Meeting
The BTF testbeam • Testbeam 10+2 days requested for beginning of June • We will try to have our DAQ based on CAEN V2718 (not use default BTF one, Labview based) • We can test TOF resolutions, not rate effects M. Bonesini 10-02-06 DAQ Meeting
What we plan to test in BTF, as regards TOF FEE • reference solution (HARP-like): Harp splitter+V775 TDC + V792 QADC + L.E. discriminator • MICE baseline-1 solution: V1290 TDC + CF discriminator (Mb-1) • MICE baseline-2 solution: Harp splitter + V1290 TDC + QADC + L.E. discriminator. For the time being QADC will be V792, waiting for new CAEN QADC based on V1724, to be delivered end of this year (Mb-2) • If available: V1290 TDC + ALICE NINO chip (discriminator+integrator) M. Bonesini 10-02-06 DAQ Meeting
Some considerations for TOFFE • MICE baseline-1 solution is easy and if works minimize manpower (our more delicate issue) • we can try to adopt Mb-1 to proceed later to Mb-2 (still reduce manpower) • ALICE NINO solution requires real work: I will suggest to consider it only if Mb-1 or Mb-2 will not work • Real delicate point: choice of CF discriminator M. Bonesini 10-02-06 DAQ Meeting
What are the discriminators on the market? • L.E. discriminators • CF discriminator Not many: in my mind some models from CAEN + CF8000 from Ortec M. Bonesini 10-02-06 DAQ Meeting
Conclusions • up to now we are in schedule • but manpower is very thin and we have to avoid non-commercial solutions, if possible • BTF testbeam will be asses many points M. Bonesini 10-02-06 DAQ Meeting